How can I get my mother to stop smoking?

Start coughing..not as soon as you see her pull one out of the pack...wait about 10 seconds or so after she lights up start off with one or 2 coughs and then as she continues to smoke the cigarette cough more and more and when she finishes the cigarette stop coughing and do this every time she smokes in front of you and do not give up..this will start to play on her conscious...even if she tries to smoke in her bedroom...if you smell it start coughing as you pass buy..and not a wimpy cough..make it a loud hooping cough and then start touching your throat as if it hurts..if after about a week of doing this she has not caught the hint then
Talk to her in a respectful way..as if she is one of your friends from school and not sarcastic like many teenagers do which parents ignore and do not respect. Tell her that her smoking is really starting to bother you and would she please start smoking outside ans not while in the car with you or in the same room..once she starts to smoke outside then this will mean she will not smoke as often which means it may lead to her deciding to stop smoking all together.

Show her pictures of what lungs of smokers look like.
leave the room every time she lights one
you can't.....she will when she is ready and not before...
Kill her, that always seems to work. But if you love her, tell her that her habit is something that you detest and that you are afraid that it is ruining your relationship with her and that you fear for her health and that she should come crying to you when she has to be taken care of when she is old.
You can't. She's gotta want to stop smoking for herself and for the right reasons.
Use a fire extinguisher on her the next time she lights up.